Barcode Quality Improvement Program – a “cure” for incorrect barcodes

The Institute of Logistics and Warehousing (ILiM) – the GS1 Poland national organization is the only institution in Poland authorized to admit companies and institutions from Poland into the GS1 system and to assign them numbers within the GS1 system, encoded in barcodes such as EAN-8 and EAN-13. These codes are essentially placed on every product package sold in retail. Since the efficiency of automatic identification systems operating in retail chain stores and elsewhere depends on their quality, continuous supervision of this quality is essential. One of the duties of the GS1 Poland national organization is to supervise compliance with international rules for marking goods with GS1 barcodes in Poland. In connection with this, ILiM has launched a barcode quality improvement program. As part of this program, free examinations were conducted in retail chains. The primary goal of these examinations is to eliminate codes that are incorrect in terms of quality, i.e., not produced in accordance with the PN-ISO/IEC 15420:2006 standard (replacing the PN-EN 797+AC: 1997 standard) and the “GS1 General Specifications”. The elimination of errors is carried out by checking the quality status of GS1 barcodes on packaging present in trade. For this purpose, Institute employees use barcode verifiers → Fig. 1. Furthermore, actions taken under the program aim to identify manufacturers who unlawfully (without an agreement with ILiM) use barcodes with the 590 prefix (these are codes found on Polish goods). This identification is possible through the analysis of product databases of Polish goods obtained from retail chains.

Many retail chains in Poland participate in the code quality improvement program, striving to eliminate incorrect codes and thereby improve the quality of services provided to their customers. These include, for example, “Makro Cash and Carry”, “Tesco Polska”, “Carrefour Polska”, “Geant Polska”, “Praktiker Polska”, “Ahold Polska”, “REAL”, “Jeronimo Martins Dystrybucja”, “Alma Market”, “E.Leclerc”, etc. Any retail chain that applies to ILiM can join the program. Chains participating in this program receive reports from the examinations conducted within them.
As part of the barcode quality improvement program, approximately 90% of codes whose quality was questioned in retail chains have been improved. This contributes to shortening customer service time at the checkout, thereby reducing queues at registers and time losses caused by the need to manually enter product numbers.

As a result of research conducted over the last two years by the Institute of Logistics and Warehousing, it was determined that the problem of barcode non-readability by scanners due to poor code quality affects approximately 2% of codes found on product packaging sold in retail. Based on the aforementioned research, time losses due to this were calculated: they average approximately 4% in retail chains in Poland. At first glance, this seems small, but on the scale of an entire retail chain, it is a significant value, e.g., with 100,000 man-hours, time losses amount to 4,000 hours. It is enough to multiply this last number by the value of a man-hour to determine these losses in PLN. And yet, losses due to poor code quality are incurred not only in retail chain stores. They can also affect the entire supply chain where automatic product identification is used.

Comparing the frequency of different types of errors in codes with the first years of the code quality improvement program → Fig. 2, it can be concluded that:
1. the most frequently occurring error in barcodes remains errors in bar/space thickness. Very often, the cause of this error is damage to the print head if a label printed, for example, on thermal transfer or thermal printers (e.g., on weighed goods) is applied to the product. It should be noted here that there is a clear decrease in the number of codes with this error;
2. the tendency to use heavily reduced and downsized barcodes persists; which is caused by adding new information required by law without changing the size of the print area. This is most often done at the expense of reducing the size of the barcode, which also affects its quality;
3. the number of errors resulting from the use of margins that are too small is decreasing,
but it is still one of the more frequently occurring errors;
4. the number of errors caused by incorrect selection of the code background color and/or code bars and the associated code contrast is decreasing;
5. in principle, the following errors no longer occur:
– errors in human-readable characters placed under the code,
– barcode obscured by labels with, for example, expiration dates, prices,
– missing or incorrect check digit.

1 – Errors in bar/space thickness,
2 – Insufficient contrast
3 – Same code for products of one company
4 – Code magnification factor less than 0.80
5 – Code margin too small
6 – Incorrect background color
7 – Incorrect code location
8 – Code bars too low
9 – Incorrect code bar color
10 – Light spots (non-prints) on code bars
11 – Incorrect number under the code
12 – Packaging curvature diameter too small
13 – Obscured barcode
14 – Missing or incorrect check digit